When linking a library libA with a library libB using libtool, if libB.la
exists, libtool will add all libraries libB.la refers to (dependency_libs
field) to the linker command line and store them in the dependency_libs
field of libA.la. So everything that subsequently links with libA will also
link to these extra libraries. This causes too much overlinking.
This commit modifies Mk/Uses/libtool.mk so it empties the dependency_libs
field in .la libraries during staging. However, because .la libraries have
very limited use when dependency_libs is empty it makes sense to completely
remove them during staging.
So with this commit USES=libtool is modified to remove .la libraries and a
new form (USES=libtool:keepla) is introduced in case they need to be kept
(dependency_libs is still emptied).

-Repocopy devel/libtool15 -> libtool22 and libltdl15 -> libltdl22.
-Update libtool and libltdl to 2.2.6a.
-Remove devel/libtool15 and devel/libltdl15.
-Fix ports build with libtool22/libltdl22.
-Bump ports that depend on libltdl22 due to shared library version change.
-Explain what to do update in the UPDATING.
It has been tested with GNOME2, XFCE4, KDE3, KDE4 and other many wm/desktop
and applications in the runtime.
With help: marcus and kwm
Pointyhat-exp: a few times by pav
Tested by: pgollucci, "Romain TartiÃ¨re" <romain@blogreen.org>, and
a few MarcusCom CVS users. Also, I might have missed a few.
Repocopy by: marcus
Approved by: portmgr

Bump portrevision due to upgrade of devel/gettext.
The affected ports are the ones with gettext as a run-dependency
according to ports/INDEX-7 (5007 of them) and the ones with USE_GETTEXT
in Makefile (29 of them).
PR: ports/124340
Submitted by: edwin@
Approved by: portmgr (pav)

Mass-conversion to the USE_AUTOTOOLS New World Order. The code present
in bsd.autotools.mk essentially makes this a no-op given that all the
old variables set a USE_AUTOTOOLS_COMPAT variable, which is parsed in
exactly the same way as USE_AUTOTOOLS itself.
Moreover, USE_AUTOTOOLS has already been extensively tested by the GNOME
team -- all GNOME 2.12.x ports use it.
Preliminary documentation can be found at:
http://people.FreeBSD.org/~ade/autotools.txt
which is in the process of being SGMLized before introduction into the
Porters Handbook.
Light blue touch-paper. Run.